Multiplex Viral Detection Platform Based on a Aptamers-Integrated Microfluidic Channel

Abstract

A polydimethylsiloxane-based microfluidic device has been developed for the multiplex detection of viral envelope proteins such as Zika and chikungunya on a single platform using aptamer–analyte interactions. The channel is integrated with microsized pillars that increase the surface area allowing more aptamers to attach to the incoming envelope protein molecules, thus increasing the overall sensitivity of the system. The working of the device depends on the formation of protein-mediated sandwich morphology that is obtained using an aptamer and aptamer-functionalized gold nanoparticle (AuNP) pair. The colorimetric signal is obtained upon introduction of silver reagents into the channel, which are selectively deposited on the AuNP surface, providing a gray contrast in the testing zone. The microfluidic channel approach successfully detected clinically relevant concentrations of Zika and chikungunya envelope proteins in phosphine-buffered saline (1 pM) and calf blood (100 pM) with high specificity using gold-decorated aptamers integrated in a microfluidic channel.

Aptamer–gold nanoparticle conjugates for the colorimetric detection of arboviruses and vector mosquito species

“…36 Because the Zika virion is similar in size to AuNPs, 24 the AuNPs may not be approaching the minimum distance needed for interparticle plasmon-plasmon interactions to ensue. Speaking to the spec-icity of the Apt-AuNP system, previous work in our lab has shown that ZIKV-E aptamers and aptamers generated against chikungunya envelope protein 1 (CHIKV-E1) show no cross reactivity in a microuidic-based assay 37 and, as stated in the Experimental section, our ZIKV-E binding aptamer was negatively selected against recombinant dengue envelope protein during SELEX. This shows that we can distinguish between avivirus and alphavirus envelope proteins though future work will incorporate live aviviruses like dengue or West Nile to see if this assay can distinguish whole virions of related viruses.…”

Current Perspectives on Aptamers as Diagnostic Tools and Therapeutic Agents

“…Aptamers with high selectivity towards viruses were attached to the micro-sized pillars of a microfluidic channel. The detection took place inside the microfluidic channel and the pillars aided in enhancing the surface of the sensing area [ 66 ]. The device works with the interaction of a protein-mediated sandwich with an aptamer-AuNP conjugate.…”

“…In this way, colorimetric aptasensor can precisely diagnose the chikungunya and Zika envelope proteins in calf blood samples (100 pM) and phosphate-buffered saline (1 pM). The schematic of the detailed colorimetric multiplex aptasensor is represented in Figure 1 [ 66 ].…”

“… The schematic representation of a sandwich-type aptasensor platform for the detection of multiple viral proteins from various viruses, for example, the CHIKV and Zika virus. The image is reused with permission from [ 66 ] . Further permissions related to the material excerpted should be directed to the ACS.…”

Nanomaterial based aptasensors for clinical and environmental diagnostic applications

“…12,13 These receptors called aptamers (a term with Latin and Greek origins: aptus meaning t and meros meaning part) have shown notable moldable selectivity for diverse target analytes, ranging from small inorganic molecules, ions, sugars, proteins, and viruses to cells. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] Such a varied target range is lacking in antibody generation due to the restriction of target receptor exposure in their native forms. This is more evident in whole cells where the surface antigens contain certain hidden trans-membrane regions, a fact which is generally not accounted for during the maturation of antibodies.…”